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BackgroundWound healing is a multifactorial procedure involving different cell types and biological mediators. The principles of wound healing are also applicable to periodontal tissues. The formation and stability of blood clots play a vital role in successful healing of wounds in periodontal tissues. The aim of the present review was to highlight the vital factors of periodontal flaps associated with blood clot stability.HighlightThe data on periodontal regeneration and wound healing have evolved greatly in light of several factors, including space for blood clots and blood clot stabilization. In periodontal osseous defects, the stability of blood clots seems critical to wound healing. If mechanical forces can be managed by wound stabilization, the gingival flap-tooth root interface may show connective tissue repair. However, compromised adhesion is susceptible to mechanical forces and can cause wound breakage and epithelialization.ConclusionThe presence of a thick blood clot may hinder the plasmatic circulation between the recipient bed and graft during the initial stage of healing, which is critical in cases of mucogingival surgery. Root conditioning can also determine the healing consequence by enhancing blood clot adhesion.  相似文献   
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Laryngopharyngeal reflux (LPR) refers to the backflow of stomach contents into the throat that is into the hypopharynx. LPR is different from classical Gastroesophageal reflux disease (GERD) in many ways. Proton pump inhibitors have become the treatment of choice even though conflicting results exists in their response. Treatment requires acid suppression to be as complete as possible and treatment failure is not uncommon. In this article we present here our prospective study of 50 patients diagnosed as a case of LPR on the basis of reflux finding score and reflux symptom index. We tried to evaluate the role of PPI in LPR management by observing the effect of PPI on reflux finding score (RFS) and reflux symptom index (RFI) during the follow up period of 16?weeks.  相似文献   
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Brain tumors in children represent the second most frequent tumors in this age group after hematologic malignancies. We highlight the demographic pattern after retrospective analysis of brain tumors in children from geographically and ethnically distinct Kashmir Valley managed in our center between 2000 and 2009. We had a total of 248 pediatric patients with brain tumors. The parameters analyzed were age, gender, location of tumors and histopathological subtypes as well as WHO grade of tumor. We also did a comparison between the frequencies of common varieties of tumor in the first and second 5-year periods. We found that 111 tumors (44.75%) were supratentorial, and 137 (55.25%) were infratentorial. The male-to-female ratio was 1.4:1. The proportions of low-grade and high-grade tumors were 60 and 40%, respectively. The most common tumor in our series was astrocytoma. The most common tumors in the supratentorial and infratentorial compartments were craniopharyngioma and medulloblastoma, respectively. Our experience reflects a different demographic profile of pediatric brain tumors as compared with other regions of the world.  相似文献   
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Purpose

Previous studies suggest that solar UV exposure in early life is predictive of cutaneous melanoma risk in adulthood, whereas the relation of BRAF mutation with sun exposure and disease prognosis has been less certain. We investigated the associations between BRAFV600E and NRASQ61R mutations and known risk factors, clinicopathologic characteristics and clinical outcomes of melanoma in a case series of primary invasive cutaneous melanoma from the Nurses’ Health Study (NHS).

Methods

Somatic BRAFV600E and NRASQ61R mutations of 127 primary invasive melanomas from the NHS cohort were determined by pyrosequencing using formalin-fixed, paraffin-embedded block tissues. Logistic regression analyses were performed to detect the associations of mutations with melanoma risk factors, and Kaplan–Meier method was used to examine associations between mutations and survival.

Results

The odds ratios for harboring BRAFV600E mutations were 5.54 (95 % CI 1.19–25.8, p trend = 0.02) for women residing in states with UV index ≥ 7 versus those residing in states with UV index ≤5 at 30 years of age. Patients with BRAFV600E mutations tended to have shorter melanoma-specific survival when compared to patients with wild type at both loci (median survival time 110 vs. 159 months) (p = 0.03). No association was found between NRASQ61R mutation and melanoma risk factors or melanoma-specific survival.

Conclusions

BRAFV600E mutations in primary cutaneous melanomas were associated with residence in locations with medium and high UV indices in mid-life. BRAFV600E mutation may be associated with an unfavorable prognosis among melanoma patients.  相似文献   
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Telomere length is important in tumorigenesis. Using quantitative real-time PCR, we prospectively measured relative telomere length in a nested case-control study within the Nurses' Health Study: 218 melanoma cases, 285 squamous-cell carcinoma (SCC) cases, 300 basal-cell carcinoma (BCC) cases, and 870 controls. We observed that shorter telomeres were associated with a decreased number of moles (P=0.002) and a decreased risk of melanoma. Women in the second and first quartiles, those with the shortest telomere length, had an odds ratio (OR) for melanoma of 0.54 (95% confidence interval (CI), 0.29-1.01) and 0.59 (95% CI, 0.31-1.13), respectively, compared with those in the fourth quartile (P, trend=0.09). There was no clear trend between telomere length and SCC risk. In contrast, we found that shorter telomere length was associated with an increased risk of BCC. Compared with those in the fourth quartile, women in the first quartile had an OR of 1.85 (95% CI, 0.94-3.62) (P, trend=0.09). The opposing associations observed should be interpreted with caution, and further research is needed to confirm these possible associations.  相似文献   
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OBJECTIVE: To estimate the value of skin biopsy in the evaluation of suspected acute cutaneous graft-vs-host disease (GVHD) after allogeneic stem cell transplantation. DESIGN: Decision analysis using parameters specified by expert opinion for skin biopsy characteristics, prevalence of acute GVHD, and value of potential outcomes. One-, 2-, and 3-way sensitivity analyses were performed. SETTING: Major stem cell transplantation centers in the United States. PATIENTS: Hypothetical cohort of patients with suspected acute cutaneous GVHD after stem cell transplantation. INTERVENTIONS: The following 3 interventions were compared: treat immediately for GVHD without performing a skin biopsy, perform a skin biopsy and treat immediately but stop treatment if skin biopsy specimen findings are inconsistent with GVHD, and perform a skin biopsy and await results of the skin biopsy specimen before treating. MAIN OUTCOME MEASURES: Number of patients appropriately and inappropriately treated with each intervention, consistency of physician-reported behavior, individualized decision analyses, and preferred intervention based on the aggregate estimates of respondents. RESULTS: The decision to treat immediately for GVHD without performing a skin biopsy yielded the best clinical outcome for the specified clinical setting and under the parameters specified by expert opinion. One-way sensitivity analyses showed that these conclusions are robust if the prevalence of acute cutaneous GVHD in stem cell recipients with rash is greater than 50%, if the sensitivity of skin biopsy specimen is less than 0.8, and the specificity of skin biopsy specimen is less than 0.9. Only 25% of physicians interviewed chose an intervention consistent with their estimates of prevalence, test characteristics, and outcome evaluations, indicating an opportunity to improve management of this important clinical condition. CONCLUSIONS: This decision analysis modeling technique predicts that in patient populations in which the prevalence of GVHD is 30% or greater (typical for allogeneic stem cell transplantation), the best outcomes were obtained with treatment for GVHD and no skin biopsy. In populations with prevalence of GVHD of 30% or less, obtaining a skin biopsy specimen to guide treatment was predicted to provide the best patient outcomes.  相似文献   
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